1. Field of the Invention
The present invention relates to a rechargeable lithium battery including a positive electrode, a negative electrode and a non-aqueous electrolyte, and more particularly to a rechargeable lithium battery incorporating the improved active material, for use in the positive or negative electrode, which undergoes a reversible electrochemical reaction with a lithium ion.
2. Description of Related Art
In recent years, intensive efforts have been made to develop rechargeable lithium batteries. Rechargeable lithium batteries are known as relying their battery performances, such as charge-discharge voltages, charge- discharge cycle life characteristics and storage capability, largely on the particular electrode active materials used. Thus extensive searches for improved electrode materials have been conducted to achieve improvements in performance of batteries.
In Japanese Patent Laying-Open No. Hei 6-275315 (1994), a rechargeable lithium battery is disclosed which employs a combination of transition metal sulfide active material and a lithium-ion conducting solid electrolyte to improve the battery performances. However, the use of tungsten disulfide (WS.sub.2) for a positive electrode material results in the reduced charge-discharge cycle life performance, because a crystal structure of WS.sub.2, serving as the positive active material, is significantly affected by insertion and release of lithium ions.